↑ 1.01.11.21.3For the purposes of numbering, a presidency is defined as an uninterrupted period of time in office served by one person. For example, George Washington served two consecutive terms and is counted as the first president (not the first and second). Upon the resignation of 37th president Richard Nixon, Gerald Ford became the 38th president even though he simply served out the remainder of Nixon's second term and was never elected to the presidency in his own right. Grover Cleveland was both the 22nd president and the 24th president because his two terms were not consecutive. A period during which a vice-president temporarily becomes Acting President under the Twenty-fifth Amendment is not a presidency, because the president remains in office during such a period.

↑Instead of being inaugurated on March 4, 1789, George Washington's first-term inaugural was postponed 57 days (1 month and 27 days) to April 30, 1789, because the U.S. Congress had not yet achieved a quorum.

↑ 7.07.17.2Later sought election or re-election to a non-consecutive term.

↑Being the first vice president to assume the presidency, Tyler set a precedent that a vice president who assumes the office of president becomes a fully functioning president who has his own presidency, as opposed to just a caretaker president. His political opponents attempted to refer to him as "Acting President", but he refused to allow that. The Twenty-fifth Amendment to the United States Constitution put Tyler's precedent into the Constitution.

↑Former Democrat who ran for Vice President on Whig ticket. Clashed with Whig congressional leaders and was expelled from the Whig party in 1841.

↑Andrew Johnson did not identify with the two main parties while president and tried and failed to build a party of loyalists under the National Union label. His failure to build a true National Union Party left Johnson without a party.